** Shares of Enact Holdings ACT.O up 4.2% at $34.77 on Thurs as co set to join S&P SmallCap 600 index .SPCY next week
** Private mortgage insurer's shares rose as much as 9.3% on session to $36.47, highest since Oct 21
** Enact to replace SolarWinds SWI.N in SPCY effective Weds, Apr 16, the S&P Dow Jones Indices said
** Turn/River Capital acquiring IT software firm SolarWinds in $4.4 bln deal expected to close soon
** Raleigh, North Carolina-based Enact has ~151.4 mln shares outstanding for ~$5.3 bln market cap, per LSEG data
** With move on Thurs, ACT shares up ~7% YTD and up ~17% over the past 12 months
** Of 6 analysts covering the stock, 2 rate "strong buy", 1 rates "buy" and rest "hold"; median PT is $38.50 - LSEG
(Lance Tupper is a Reuters market analyst. The views expressed are his own)
((lance.tupper@tr.com 1-646-279-6380))